Since My Husbands Heart Valve Replacement 10 Weeks Ago, He

Since my husbands Heart Valve Replacement 10 weeks ago, he can't sleep. He sleeps 2-4 hrs, then wide awake. We've tried presc. pills and now over the counter ZQuill or Tylenol PM. Have a lavender scent in bedroom. Also, terrible night sweats! A fan blows on him from the side and one above us and he sokes the pillow. Did this surgery mess up his hormones too????